The influence of earthworms on soil fertility. I. Earthworm populations found in agricultural land near Adelaide

Abstract

The most common earthworms in the agricultural land examined were the introduced lumbricids Eisenia rosea (Sav.) and Allolobophora caliginosa (Sav.). Pastures established for 6 or more years carried an average of 80 g of worns per 1000 g annual production of dry herbage. Very few worms were found in soil which had been cropped on a tm-o course rotation for 30 years. Where land was cropped on a four course rotation of 2 years' ley/fallow/wheat, the weight of worms fluctuated during the rotation. After the fallow and crop years the weight was only a quarter of that found on permanent pasture. but at the end of the ley the weight almost equalled that on the permanent pasture. The earthworms mere active for about 24 weeks each year. In winter, when the worms were feeding, most were in the top 15 cm of soil. As the soil dried out in spring the worms tunnelled more deeply and aestivated at depths of 15-60 cm.